BUENOS AIRES, Argentina – Some parts of South America are being hit by devastating floods, while others are being affected by severe drought that experts say are caused by this year's powerful El Nino weather phenomenon.

Authorities in Argentina said Thursday that 10,000 people were evacuated in Entre Rios province after rains swelled the Uruguay River to its highest level in nearly a century. The provincial governor says up to 20,000 more people could be evacuated in the next hours.

Flooding caused by heavy rains also has led to the evacuation of an estimated 100,000 people in Paraguay and more than 4,000 in Uruguay.

To the north in Colombia, an exceptionally strong El Nino has had the opposite effect, creating a drought that officials fear will empty important reservoirs used for generating electricity.